MTU MS15027/02E Operating Instuctions page 140

655 – AL TecJet Comm Lost
Red alarm.
Associated parameter 1.4540.996
Cause
CAN bus communication to gas
control valve faulty (alternatively
a stepper motor with gas mixer
can be installed).
656 – AL ProActA Comm Lost
Red alarm.
Associated parameter 1.4550.096
Cause
CAN bus communication to
throttle A faulty.
657 – AL ProActB Comm Lost
Red alarm.
Associated parameter 1.4550.196
Cause
CAN bus communication to
throttle B faulty.
658 – AL NOxA Comm Lost
Yellow alarm.
Associated parameter 1.4560.096
Cause
CAN bus communication to NOx
sensor A faulty.
659 – AL NOxB Comm Lost
Yellow alarm.
Associated parameter 1.4560.196
Cause
CAN bus communication to NOx
sensor B faulty.
140 | Troubleshooting | MS15027/02E 2015-04
Corrective action
1. Check cabling.
2. Check power supply.
3. Restart ECU, EMU & gas control valve.
4. Check settings using device-specific dialog software (XD11).
Corrective action
1. Check cabling.
2. Check power supply.
3. Restart ECU, EMU & throttle A.
4. Check settings using device-specific dialog software (XD50.1).
Corrective action
1. Check cabling.
2. Check power supply.
3. Restart ECU, EMU & throttle B.
4. Check settings using device-specific dialog software (XD50.2).
Corrective action
1. Check cabling.
2. Check power supply.
3. Restart ECU, EMU.
4. Replace sensor.
Corrective action
1. Check cabling.
2. Check power supply.
3. Restart ECU, EMU.
4. Replace sensor.